#include<stdio.h>

int Sum(int a , int b)
{
    int flag  = 0;
    int result = 0;
    for(int i = a;i<=b;i++)
    {
        result+=i;
    }

    return result*flag;
}

int main()
{
    int start = 1;
    int end = 100;
    printf("i will begin!\n");
    int n = Sum(start , end);
    printf("reuning done,result is :[%d-%d]=%d\n" , start , end ,n);
    return 0;
}
